About this Unit
Amphibious Construction Battalion ONE (ACB-1) was commissioned on July 16, 1943, at Camp Peary, Virginia, as part of the U.S. Navy’s effort to support amphibious operations during World War II. The unit played a vital role in constructing and operating pontoon causeways, beachhead facilities, and support installations during major Pacific campaigns, including the invasions of Iwo Jima and Okinawa. In the decades following World War II, ACB-1 continued to support U.S. Navy and Marine Corps missions in Korea, Vietnam, and more recent operations, providing essential logistical and engineering capabilities. Today, ACB-1 remains based at Naval Amphibious Base Coronado, California, standing ready to deliver specialized amphibious construction and support wherever needed.
Historical Facts
• Origins in WWII: Amphibious Construction Battalion ONE (ACB-1) was originally commissioned on 16 August 1943 as the 104th Naval Construction Battalion, before being redesignated as ACB-1 in 1950.
• Normandy Landings: Elements that would become ACB-1 participated in the D-Day landings at Normandy, providing vital beachhead construction and logistics support.
• Korean War Innovation: ACB-1 pioneered pontoon causeway and pier construction under hostile fire during the Inchon landings in 1950, facilitating rapid offloading of men and material.
• Vietnam War Service: From 1965 to 1972, ACB-1 constructed and maintained vital logistics facilities, piers, and causeways throughout South Vietnam, earning several unit commendations.
• Port Hueneme Homeport: ACB-1 is based at Naval Base Ventura County, Port Hueneme, California, a historic hub for Navy Seabees and amphibious operations.
• Joint Operations: ACB-1 regularly deploys with the U.S. Marine Corps and Army, supporting joint and combined exercises and operations worldwide.
• Humanitarian Missions: ACB-1 has provided disaster relief after tsunamis, hurricanes, and earthquakes, including significant work during Operation Unified Assistance after the 2004 Indian Ocean tsunami.
• Modular Causeway Systems: ACB-1 specializes in deploying Improved Navy Lighterage Systems (INLS) and modular causeways, enabling logistics over the shore (LOTS) where no port exists.
• Decorated Unit: ACB-1 has received multiple awards, including the Navy Unit Commendation, Meritorious Unit Commendation, and various campaign medals for its service in combat and peacetime.
• Seabee Legacy: As a Seabee unit, ACB-1’s motto is "We Build, We Fight," reflecting its dual capability to construct critical infrastructure and defend itself in combat zones.
